Field-induced quantum barrier crossing: classical chaos and weak localization

Abstract

Based on a model double-well oscillator driven by a classical field we have carried out a classical and quantum mechanical analysis of field-induced barrier crossing. We have shown that classical chaos significantly enhances the quantum barrier crossing rate as well as the quantum fluctuations. The classical chaos is also manifested through a kind of weak dynamic localization at the barrier top (due to the time reversal symmetry of the Hamiltonian) in the time scale relevant for barrier crossing dynamics, which is much shorter than the asymptotic time scale required to resolve the quasi-energy levels of the system.